1. Field
The present disclosure relates to an organic light emitting display device which can emit lights having desired wavelengths, respectively, and thus can emit white light with high efficiency.
2. Description of the Related Technology
An organic light emitting display device is a self-luminous display device which emits light through application of a voltage to an organic light emitting layer that is interposed between a positive electrode and a negative electrode.
In such an organic light emitting display device, one of the positive electrode and the negative electrode is generally used as a reflection electrode and the other is used as a transparent electrode. Light emitted from the organic light emitting layer is generally provided in one direction.
For example, if a positive electrode that is used as a reflection electrode is formed on a substrate, an organic light emitting layer is formed on the positive electrode, and a negative electrode that is used as a transparent electrode is formed on the organic light emitting layer. Then, light emitted from the organic light emitting layer is provided in the direction of the negative electrode. An organic light emitting display device having such a structure is called a top-emission organic light emitting display device.
As another example, if a positive electrode that is used as a transparent electrode is formed on a substrate, an organic light emitting layer is formed on the positive electrode, and a negative electrode that is used as a reflection electrode is formed on the organic light emitting layer. Then, light emitted from the organic light emitting layer is provided in the direction of the positive electrode (or in the direction of the substrate). An organic light emitting display device having such a structure is called a bottom-emission organic light emitting display device.
When the positive electrode is used as a reflection electrode, it is typically formed of metal having high reflectivity.